The present invention relates to a communication control system for an image recording apparatus.
Conventionally, a recording apparatus which receives externally input image data, and obtains a reproduced image is known. In a recording apparatus of this type, e.g., an ink-jet printer which comprises multi-nozzles for discharging an ink, and can record a color image by discharging corresponding color inks from the nozzles onto a recording medium on the basis of externally input print data, multi-nozzle heads corresponding to the number of color inks are mounted, and a color image can be recorded by sequentially discharging inks from the nozzles on the basis of external image data (print data).
The multi-nozzle printer can record a binary image by executing binarization processing based on color print data. In this case, the following data communications (1) and (2) are often performed.
(1) A binary image obtained by converting multi-value image data into a binary image by an external apparatus, e.g., a host computer is transmitted to a printer, and is recorded on a recording medium.
(2) An external apparatus, e.g., a host computer transmits multi-value image data to a printer, and the printer records a binary image on a recording medium while executing binarization processing of the multi-value image data.
In particular, when binary image recording processing is performed based on multi-value image data by the method (2), the printer comprises an overlap memory having a binarization processing function, multi-value image data of a peripheral portion exceeding a print width are written in the overlap memory to overlap the data of the print width, and binary image data corresponding to the print width are generated on the basis of stored pixel data.
However, the external apparatus as a communication source side must check the overlap memory capacity on the basis of the type (registered) of a printer to be connected, and cannot detect the overlap memory capacity if the printer is a nonregistered printer. Thus, the external apparatus must execute transfer sequential processing for, e.g., designating the type of printer, and a considerable time is required until a desired binary image is obtained.
Furthermore, when some of the multi-nozzles suffer from ink discharging errors, print processing is interrupted, or is continued with errors. Thus, a desired color image cannot often be obtained.
Some ink-jet printers can record data on a plurality of types of sheets such as roll paper, cut sheets, OHP sheets, and the like. However, such printers must change a print sequence depending on the types of sheets to be subjected to recording, and must comprise, e.g., large capacity image memories to cope with this problem.